Addressed review comments.

RocksDB introduced in 3.7.0 convenience methods
for getting ColumnFamilyOptions and DBOptions
instances from predefined configuration structures.

There is now also a method in RocksJava to load DBOptions
as well as ColumnFamilyOptions from a predefined Properties
based configuration.

Summary:
The very last reference happens in DBImpl::GetOptions()
I built with both DBImpl::GetOptions() and ColumnFamilyData::options() commented out

Test Plan: make all check

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D29073

Summary: We should not reference cfd->options() directly!

Test Plan: make release

Reviewers: sdong, rven, igor, yhchiang

Reviewed By: igor, yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D29061

Summary:
Add unit support in options helper so we can specify, e.g., 10m for
10 megabytes.

Test Plan: Updated options_test

Reviewers: sdong, igor, ljin

Reviewed By: ljin

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D28977

[RocksJava] GetIntProperty in RocksDB

Improved comments in RocksDB getLongProperty methods,
to describe the behavior more detailed.

Expose GetIntProperty methods to RocksJava. As the integer(64-Bit)
value is no integer in Java the method is aligned with the return
type which is long.

[RocksJava] JavaDoc corrections - Java8

This commit solves build problems in Java8 due
to wrong JavaDoc.

Summary: Fixed a bug which could hide non-ok status in CompactionJob::Run()

Test Plan: make

Reviewers: sdong, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D28995

Use correct classloader in Java NativeLibraryLoader

Summary:
Improve the comment in InfoLogLevelTest.java

Test Plan:
make rocksdbjava

[RocksJava] LogLevel support in Options

Native Library

[RocksJava] Bump version to 3.8.0 in rocksjni.pom

Summary: This way we can gurantee that old MemTables get destructed before DBImpl gets destructed, which might be useful if we want to make them depend on state from DBImpl.

Test Plan: make check with asserts in JobContext's destructor

Reviewers: ljin, sdong, yhchiang, rven, jonahcohen

Reviewed By: jonahcohen

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D28959

It's now possible to set a LogLevel in Options and
DBOptions to control LOG verbosity.

Cuckoo table options missing in the C interface

[RocksJava] Test framework support

+ 7% coverage + 3% branch coverage

Summary:
As we had the discussion some weeks ago. Java needs a test framework and should support code coverage analysis. This pull request includes:

    Move Tests from main method functionality to Junit4
    Move WriteBatchTest to test package
    Adjust the Makefile to run Junit4
    Download dependencies from Make (once if not-present)
    Adjustment of the rocksjni.pom to run coverage analysis using jacoco
    Javadoc excludes now tests
    Two bugfixes regarding GC cleanup which came up within the test runs

Make can be used as beforehand to build and run RocksJava. make test runs tests using the command-line version of Junit4.

Maven can be used to retrieve code coverage reports using mvn -f rocksjni.pom package. Code coverage reports can then be found as usual in the site folder.

Testing libraries available within Java

    Junit4 (incl. hamcrest-core dependency)
    AssertJ (providing fluent syntax for assertions, cglib dependency)
    Mockito to provide mocktests

Libraries as said before are not statically within this commit or filesystem instead they are downloaded using curl. Make checks if files are present, if so it will perform tests without downloading the libraries again.

Note: Libraries are only necessary to compile & run tests.

Next steps after merge:

    Get the maven build into travis-ci and coveralls.io
    Filling up the missing test spots (based on coverage data)

Test Plan:
make rocksdbjava
make jtest

Reviewers: yhchiang, ankgup87, adamretter

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D28209